The present invention is directed to the field of containers and specifically to the field of tamper resistant containers.
The use of tamper resistant containers is not only desirable but essential in certain applications. In particular, the sealing of containers in a manner to resist tampering with the contents, or at least provide a mechanism where any tampering will be readily apparent, is critical in those applications where there is a need to maintain the chain of custody of such contents. This usually requires that the container be sealed in a manner which would minimize accessibility to the contents, or at least visually indicate if such access has been obtained.
The use of tamper resistant containers is particularly important in the fields of medical and criminal investigations, where maintaining the chain of custody is of paramount importance. For example, in criminal investigations the testing of substances to determine whether the same is a controlled substance requires that the identity of the substance be reliably maintained throughout the testing and storage of such substance.
This maintenance of the chain of custody is especially important when the substance and its identity is to become a matter of record at trial. Thus the substance must be held in a container which minimizes the possibility, or at least reliably evidences tampering with the contents.
The use of such tamper resistant containers is also important in the field of medical investigations. For example, the identity of blood/urine samples which are being tested for various infectious diseases and/or chemicals must be maintained in order to ensure that the specimen remains as collected. This allows for a confirmation of the reliability of the test procedures, and is especially necessary in order to ensure that the particular individual from which the blood and/or urine is taken can be properly identified. Thus it is necessary to maintain such specimens in a tamper resistant container. The importance of the reliability in medical testing has recently gained particular importance with such testing being conducted as part of employment programs.
Another important application for tamper resistant containers is the use for storage or transportation of medical specimens which may include infectious diseases. For example, when transporting blood samples which are to be tested for the AIDS virus it is desirable to maintain the integrity of the individual specimens and also to prevent accidental contact with the specimens. A tamper resistant container will ensure not only the integrity of the specimens, but will also minimize unwarranted contact with the specimens contained therein.
Presently available tamper resistant containers are fastened shut using wire or plastic ties. For example, a container constructed from two halves includes eyelets formed along a common side of each container half which are aligned when the container is shut. Individual ties are then wrapped through the aligned eyelets with their respective ends being sealed together using material, e.g. a piece of wax or solder. The container can only be opened by breaking the seal holding the wire or plastic tie together, which is easily detected.
Other presently available containers are formed with a one way insertable plugs which snap through apertures formed in each of the container halves. That is, each half of the container is formed with separate apertures which will be aligned after the container is closed. The plugs are typically formed to easily fit through the apertures but cannot be removed therefrom.
An example of such a container with a plug is seen in FIG. 7, generally at 10. The plug 12, includes first and second halves which are disposed at ninety degrees to one another. The first half, seen at 13, is a flat rectangular body, with the second half formed with a central stem which extends out from the rectangular body. This central stem 15 has integrally formed from two opposite sides individual prongs 17 and 17'.
These prongs 17 and 17' extend from a common end with the central stem 15 and project therefrom in a direction generally parallel to the central stem 15 and to each other. These prongs 17 and 17' are formed with an outer edge which angles outward from the common end away from the central stem. The construction of the second half in this manner allows for the movement of the prongs 17 and 17' towards the central stem 15 by applying pressure against the outer edges of each prong 17 and 17'. After this applied pressure is removed the prongs 17 and 17' move freely in the opposite direction away from the central stem 15. This re-positions the prongs 17 and 17' in the original positions with respect to the central stem 15.
The container 10 includes a cover section 14 and base section 16 which are each formed with at least first apertures 18 and 19 which are brought into alignment when the cover 14 is fitted onto the base 16. By pushing the second half of the plug 12 through the aligned apertures 18 and 19, the prongs 17 and 17' are moved inward. That is, as the two outer edges of the prongs 17 and 17' slide along the sides of the apertures 18 and 19 the angular relationship of these outer edges exerts the necessary pressure against such edges. This pressure causes the prongs 17 and 17'to move inward towards the central stem 15, thus allowing the passage of the second half through the apertures 18 and 19.
Once passed through the apertures 18 and 19 these prongs 17 and 17' return to their original positions preventing the removal from such apertures 18 and 19. When entry is desired into the container 10 the first half of plug 12 is broken away from the second half. This is accomplished by forming the plug 12 from a relatively brittle material which is easily broken. This breakage is easily observed and indicates the possibility of tampering with the contents.
Another application for which tamper resistant containers may be useful are those applications wherein child resistant caps are now presently being used. That is, certain containers are provided with caps or covers which require a specific manipulation to allow removal. In place of constructing each individual container with a child resistant cover, a multiple number of such containers can be inserted with a box like container which is secured in the manner discussed above. This would provide the desired child resistance afforded by the individual container covers at a lesser expense.
While the above discussed containers do provide for a degree of resistance to tampering, or at least minimize undetected tampering, these containers do have some limitations. In particular, it has been found that both the wire and plastic ties and insertable plugs can be removed and replaced with an identical tie or plug without any detectable difference. Thus the contents can be tampered with without detection. This defeats the very reason for using such containers.